The invention relates to a micro-surgical cutting instrument of the type configured as scissors, which includes a housing formed as a handle, and a device disposed in the housing for an axial sliding movement of a probe, that is configured as a hollow needle and which axially supports a rod with the cutting device disposed at the distal end of the rod.
The present invention is generally directed to surgical procedures and special problems that occur when such procedures are carried out in body cavities of a living being. For example, certain difficulties occur when treating the eye of a living being for retinal diseases. Such diseases oftentimes appear in conjunction with hypertonia or vascular changes. In the course of such diseases, venous branch occlusions (phlebemphraxis) can occur in an area where veins and arteries cross each other and are surrounded by a substantially transparent skin sheath or membrane, whereby the artery which overlays the vein can press on the vein in such a way that the vein becomes pinched. By separating (cutting) and removal of the skin sheath, such venous branch occlusions can be eliminated or can even be prevented.
When carrying out microsurgical procedures of, for example the afore-described type, in addition to a steady hand when handling the instrument, precise functioning of the instrument used for this purpose is required. Thus, it is particularly important for this purpose that the instrument is designed, so the diseased tissue can easily be reached and grasped with the instrument and that the instrument can be held steady in the surgeon's hand over a along period of time and that the instrument's cutting position can be visually easily recognized.
The generally known prior art instruments have certain drawbacks such as, for example, they can damage the tissue due to improper configuration of the instrument's cutting blades; or, even prior to cutting the tissue, the blades can deform the tissue in a manner rendering it unsuitable for the cutting action, or the cutting blades unexpectedly retract during the procedure. In many ways these known cutting instrument no longer fulfill the requirements of modern microsurgery and are not suited for surgery on delicate tissue structures, in particular for surgery on the delicate tissue of the retina.
It would thus be desirable and advantageous to provide an improved surgical instrument which overcomes the above-described shortcomings.